Over 500,000 residents of Naivasha Sub- County have a reason to smile after installation of a Sh1 billion system that will supply them with fluoride free drinking water.
Governor Lee Kinyanjui said overreliance by residents particularly in Longonot and Maai Mahiu areas on underground water sources had exposed them to a high risk of suffering from dental fluorosis and crippling skeletal deformities.
He said there were plans to increase the number of alternative fluoride-free water sources in the devolved unit, noting that there were high concentrations of fluoride in the county’s boreholes sometimes way above the 1.5 milligrams per litre allowed by the World Health Organization (WHO).
“Residents of Naivasha will for the first time enjoy piped fluoride-free water from Malewa River. In the meantime, our experts have been working round the clock in all the 11 sub-counties to identify fluoride-free areas that will see more boreholes established to help meet rising water demand,” stated the Governor.
Underground water sources in Naivasha, Njoro, Nakuru Town West, Gilgil, Nakuru East and Bahati Sub-Counties have been singled out as having high concentrations of fluoride in Nakuru.
The situation is worse in Naivasha where boreholes are the main source of water with a recent study done on the area’s boreholes last year indicating that most of the private boreholes in Naivasha have fluoride levels way above the recommended 1.5 mg/litre.
According to the study commissioned by the County Government, fluoride levels range between 2.15mg/Litre to as high as 6.5 mg/Litre in the fifteen boreholes sampled during the analysis carried out at the water quality testing laboratory.
In an interview, Kinyanjui said that his administration is also committed to minimizing the impact of fluoride in all the sub-counties, by ensuring that its Water Service Providers were supplying “blended water” to the residents which is within the recommended levels by WHO.
“We have two river sources, one emanating from Dundori where at the moment we get about four million litres per day and the other water from Malewa. The water from these rivers is channeled into our main treatment works where we do the blending with water from underground sources,” he explained.
Nakuru Water and Sanitation Services Company (Nawassco) sources its water from 25 boreholes; one in Kiondo, eight in Kabatini, three in Nairobi Road, five in Baharini, and eight in Olobanitaa within the county.
Governor Kinyanjui said the company serves a population of more than one million during the day and approximately 530,000 people during the night.
The Naivasha Water and Sanitation Company Limited (Naivawasco) gets its raw water from 13 boreholes, located in six production sites. It serves a population of about 170, 000 out of the 198,444 people, according to the 2019 census.
Kinyanjui further stated that his administration was supporting initiatives towards developing water distribution networks that includes water kiosks fitted with defluoridation filters using “local bone char technology.”
The bones are put through four steps to transform them into defluoridation material. First, they are burnt, then crushed and sieved before being washed and then dried.
The final product is a greyish and porous granular material whose main components are calcium phosphate, calcium carbonate and activated carbon, and it is this peculiar chemical composition, the developers believe, that gives the char its specific ability to absorb fluoride from water.
“These filters have reduced fluoride levels from 9 mg/litre to below 1.5 mg/litre, greatly improving the quality of consumption water and reducing the risk of fluorosis and a host of other harmful health effects. We are encouraging adoption of these small bone char defluoridation units, some which can be used at home,” says Kinyanjui.
Fluoride is a chemical compound that occurs naturally on the earth’s crust. It is formed during rock formation and is a chemical ion of chlorine.
“All rocks have fluoride but the quantity differs, depending on where the rock is located. During water formation within the rocks, fluoride naturally becomes one of its components,” says County Chief Officer for Environment, Energy and Natural Resources, Mr Kiogora Muriithi.
However, the quantity of fluoride in the water depends on the saturation of the chemical compound in the rock or layer. So, some have very high concentration while others have only small amounts,” Muriithi added.
Scientists say millions of Kenyans are at risk of serious bone defects and dental discolouration as a result of high levels of fluoride in their drinking water.
The risk is made worse by the fact that as the rest of the world moves to treated and piped water systems, more than half of Kenyans (56 per cent) still rely on underground water, which the Kenya National Bureau of Statistics (KNBS) defines as, among others, water fetched from wells and boreholes.
Data from Kenya Society for Fluoride Research further shows that 19 million Kenyans suffer from fluorosis, affecting the teeth and/or skeleton, depending on the length of time one has been exposed to water with a high concentration of fluoride, and their geographical location.
Three years ago, scientists conducted a study on the levels of fluoride in Gilgil and Njoro Sub-counties.
The research conducted by Patrick Kirita Gevera and Hassina Mouri both of Department of Geology, University of Johannesburg and Godfrey Maronga from Department of Restorative Dentistry, University of Western Cape sampled dental patients at St. Mary’s Hospital-Gilgil and Egerton University-Njoro Dental Clinic.
The findings were startling with the prevalence of patients with dental fluorosis who visited St. Mary’s Hospital-Gilgil for dental health care hitting 86 percent, where 54percent of the patients suffered from mild to moderate dental fluorosis.
32 percent had severe dental fluorosis, whereas the prevalence of dental fluorosis in patients below the age of 14 years was higher at 92 percent than in older patients which the study established stood at 85.56 percent. Dental fluorosis mainly affects children with developing teeth, although it affects adults as well.
“There is no cure for dental fluorosis. It can only be prevented. The condition of damaged teeth cannot be restored. In adults, the teeth lose their white colour and develop yellowish spots within two years,” the researchers noted.
“Depending on the quantity of the fluoride, the effects may begin to show two years after one starts consuming water with high levels of fluoride,” states the research report.
At Egerton University’s Njoro Dental Clinic, a comparative analysis revealed a much higher dental fluorosis prevalence rate of 100 percent for patients below the age of 14 years relative to the older patients at 79.49 percent.
“While a high number of cases of dental fluorosis from both healthcare facilities were reported in patients residing in Njoro, Nakuru town, Gilgil and Bahati, some cases were reported from Solai and Rongai. The results seem to suggest a much higher occurrence of dental fluorosis within the younger population group.
This implies that rapid population growth and urbanization puts more pressure on public water resources which leads to a strong reliance on fluoride contaminated groundwater and the concomitant increased cases of dental fluorosis.
“There is a need for a change of County Government policy to enhance access to safe water and public education on fluorosis in the areas that were under investigation,” recommends the research team.
According to the WHO, ingestion of excess fluoride, most commonly in drinking water, can cause fluorosis which affects the teeth and bones. “Moderate amounts lead to dental effects, but long-term ingestion of large amounts of fluoride can lead to potentially severe skeletal problems,” says the WHO.
The WHO says dental effects of fluorosis develop much earlier than the skeletal effects in people who have been exposed to large amounts of fluoride. “Clinical dental fluorosis is characterized by staining and pitting of the teeth. In more severe cases all the enamel may be damaged,” says the WHO.
The global health body however adds that fluoride may not be the only cause of dental enamel defects. “Enamel opacities similar to dental fluorosis are associated with other conditions, such as malnutrition with deficiency of vitamins D and A or a low protein-energy diet. Ingestion of fluoride after six years of age will not cause dental fluorosis,” states the WHO.
By Anne Mwale and Elizabeth Simiyu
